This invention relates generally to cable tray systems and, more particularly, to ladder-type cable tray systems.
Conventional ladder-type cable trays are typically suspended from a building support structure in non-residential buildings to carry electrical cables, such as power, telephone, and computer cables. The cable trays are generally shipped to construction sites in sections, with a typical section being twenty feet long. To install the cable tray system, two sections are suspended from the building support structure. The sections are then positioned end-to-end and securely fastened together by threaded fasteners, such as screws or bolts. After the two sections are securely fastened together, another section is suspended from the support structure and securely fastened to one of the first two sections. This procedure is repeated for every additional section of the cable tray system.
A difficulty associated with such cable tray systems is that adjacent sections must be securely fastened together to maintain alignment of the adjacent sections. The sections must be secured together before an additional section may be added. The installer must hold the two sections in alignment with one hand while using the other hand to operate an appropriate tool, such as a screw driver, to secure the sections together. This can be difficult since the sections are typically quite bulky and cumbersome to manipulate. Also, since installation of the cable tray requires alternating back and forth between the suspending procedure and the securement procedure, installation of the cable tray system is time consuming. Further, the installer must constantly carry the tools necessary to perform both procedures. Moreover, since the fasteners function to hold adjacent rail sections together, the fasteners must bear the load placed on the rail sections. Failure of the fasteners of even one rail section will cause the section to separate from an adjacent section.